I must say, shows in NYC without smoke are pretty awesome. it's definitely a better environment without it, and it feels like fewer people are smoking.
I'm a former smoker who will still have one when I drink a certain amount...if there's no one smoking around me, I don't even think about it.
I'm wary of a ban. I'm torn, too -- selfishly, it helps me out to have no smoking allowed, but I remember how much I loved and enjoyed my cigs during a show (the thing to remember is, at a show, there's liquor, and for many smokers the liquor makes it nigh near impossible to refrain from smoking as well).
Tough question, very tough question.
